Foldable aircraft wing with mechanism for operating and locking the outboard section thereof



Oct. 4, 1955 A. J. HANDEL 2,719,682

FOLDABLE AIRCRAFT WING WITH MECHANISM FOR OPERATING AND LOCKING THE OUTBOARD SECTION THEREOF' ATTORNEYS Oct. 4, 1955 A. J. HANDEL 2,719,682

FOLDABLE AIRCRAFT WING WITH MECHANISM FOR OPERATING AND LOCKING THE OUTBOARD SECTION THEREOF' Filed Feb. 16, 1953 3 Sheets-Sheet 2 A 2s ,O

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2 1 J J l lf-/l-ll i 1"" w L I I IIII` [-8- E 3o 2 )N gf Il IW: i l, JNVENTOR. E l l l 9 l' l l i, I ALFRED J. HANDEL.

' BY Y ATTORNEYS Oct. 4, 1955 A. J. HANDEL 2,719,682

FOLDABLE AIRCRAFT WING WITH MECHANISM F OR OPERATING AND LOCKING THE OUTBOARD SECTION THEREOF Filed Feb. 16, 1955 3 Sheets-Sheet 3 53 49 SO 5l INVENTOR.

ALFRED J. HANDEL ATTORNEYS 'lockedpr'ior to'llight, by afratherieomplicatedmechanism,

'cation continues. The novel tfeatres willbe pointe'diout United States Patent Oice 2,719,682 Patented Oct. 4, 1955 2,`71/9,6s"2 FoLnAnLE AmCRAFT WING non oPERATlNG AND `Loon-ING -THE our- Bonnie sncrroN THEnEoF Alfred J. Handel, lamedacaiif. Application February 116, 1953, serial 10.331164 4 claims. (ci. 244-49) The present invention'relates to'impiovernents in afoldable aircraft Wing with mechanism for operating and locking the outboard section thereof. AIt'consists of the combinations, constructions and arrangement of parts, as hereinafter described and claimed. I. e e d' ln order to conserve storage space for aircraft, such as fighters aboard carriers, it'ha'sbee'nthe practice for many years to provide foldable wings onsuchplanes. Broadly speaking, this type of a wing 'includesinboafrd and outboard sections, which are hingedly's'cured together. A' The outboard section is swingable from a lowered active posi tion, in which it forms a `lateral continuationof theinboard section, 'into an upwardly-extending raised or inactive position. Y Y n y Moreover, the `inboard 'andoutbord 'sections areinterand they must be` unlocked before the outboardfsection maybe folded. Also, va separate apparatus is-prvided in conventional designs for raisingand:lowering'theioutboard section, which indeedis fa'rifro'm'beingsirriple. 4 y

As the Ycardinal object of lthis invention, itis proposed to provide hereina mechanism forlo'ckingidown the volit- 4board section of a foldableaircraft 4vwing'so :as jto obtain anextremely 'strong lock, `yet`vat, `the-sertie time keep this mechanism as small, ecient and compnet 'as'pos'sible dt is further proposed to provideasingleactuator:in each wing that is designed in suchlalm'anner 'asfto'accornsections, withtliis saine inechariilsmservingthe additional Another object Y'of the inv/endlos room inboard for guns, ammunition boxes, fuel, tanks, etc., whi'chmay'beplacedin thewing.

Other objectsfand advantages'will ppearsthef's'peciin the claimshereuntoappended.

Drawings 'For a better understanding of 'the invention 'here involved, reference should be had (to the 'accop'a'nying drawings, forming part of this application, in'whilch:

Figiirepl is 'ahori'z'ontal sectional viwltkenthrough my foldable 'aircraft wing, lwith 'the 'outboard 'section locked down in active position toekteridlterally beyond the'inboard section; v

Figure 2 is a fragmentary view similart'o'I-igurefl, but disclosing the outboard section unlocked "and ready for being folded into yan "upwardlyiertendingposition;

Figure 3 is apvertical sectional view taken along the plane 1li-lli of Figure 2 just'in'back'ofithefrzer sparz;

Figure 4 is a vertical "sectional View taken along theline 'LIV- lV of Figure l, and disclosing t'h'eforwad s'p'arfrom the insidefof the ektendedwing; n

Figure 5 is a view corresponding tolFigureZi/but'illu'srating theo'utbeard gestionar-the wijng'fised int an 'inactive position Vextending upwardly 'from the inbord Y N d 'Y toplace-theietuato'r 45 jin theo'utboard section of 'the wing to 'allowlallpos'sible 2 section, :and further including a diagrammatic disclosure ofa suitable 'control mechanism -for operating the winglockin'g and winglmoving actuator; p

Figuren shows this `Vactuator mechanism adjusted-for lowering ythe outboard section of the wing into prolongation with theinboard section thereof; and

Figure 7 vis a top plan `View of a wing-locking toggle mechanism, as observed from the plane VII-VII 0f Figure 4, this mechanism being provided for interlocking the'inboard and outboard sections ofthewing in active flying relation'with one another.

While Ihave shown only thepre'ferred yformofrn'y invention, it should be understood that various chfaiigesfor modifications, may be made within the scope 'of the'anne'xed'c'laims without departing from the spiritthereof.

Detailed description Referring to the drawings, it will be noted that 'I have provided a foldable wing for an aircraft, whichincludes inboard and outboard sections A and B, respectively. These sections may -be swung into alignment with kone another so as to provide a continuous wing structure, as shown in Figures '1 4, or the outboard section Bfma'y be folded upwardlyrelative to the inboard section A, `thus `requiring a reduced storage space for the aircraft, The leading and trailing edges of the wing 'are `indicated generally at l'and 11, respectively (see Figure 1).

With particularreference 'to Figures l and v2, 'there 'is disclosed front and rear`spars designatedia't C andfD, `respectively, which`extendglaterally through the'interior 'of the `wing structure. -It will be Yseen fromthe drawings that the front spar C has been shown as being about twice'as `heavy-as -Athe rear sparfD. Ther'eason for this difference nin structural strengthisdueto thefa'ctthatthe front'spar supports approximately two-thirds 4of the weight of 'an Vaircraft while in`ight. However, 'I do ynot desire 'to `be limited in dimensions or proportions.

vIn itsstructural details,-the front'sparC includes upper and lower `parts 12 and 13, respectively, which are -mounted in the inboard 'wingsection A '(see 'Figures 24 and'S). Also, ithe front spar C ldeines'upper andA lower parts 14 and `15, respectively, disposed in the'outboar'd 'sectionB-of the foldablewing. When these sectionsare moved into active flight position, such as illustrated -in Fig`ure 4, the/upper parts 12and 1`4`ofthe front spr C are arranged'in alignment with oneianother. The sameis vtrueofthe lowerparts 13 and 15`of the'front-sp'ar.

Turningnow-t'o 'the rear VsparD, it provides upperand flowerlparts `16'and 17, respectively, whichar'e contin'ed'to the inboard section A. `In'like'marinenthe'outboard section B contains upperiand llo`werfp`arts 18 and'19 of the rears'parD (seeFigu're 3). YIt will be apparentthatthe upper parts 16 and `18 are alignedwith one another, when the outboard section B is disposed in prolongation with `theiriboard section; and at the Sametime-the lowerp'arts j17and 19 occupy positions of'aligriment.

y"In'Figures kl to 5, inclusive, the inboard sectionAfhas beenfdisclors'ed as having ribs 20 fastened'to'its sparparts l2-:13 and `16--17, and an inboard airfoil -or :skin 21 `lcovers these ribs and spar parts. Likewisepthe outboard 'sectionB includes ribs '22 secured to'its spar partsll-IS and 1S-i9. 'An outboard 'airfoil or Vskin 23 covers the latter ribs c'and spar pa'rts.

Moreover, the"a:ljacerit edges Maand 23a ofthe air- `foils 2:1 and 23, respectively, are 'butted together when the wing sections A-'B loccupy 'theiractive flight positions, thereby providing a wing `joint v24 therebetween. Thisjoint slants outwardlyand downwardlyV (see'Figures 3-5) to set a wing-lock toggle mechanism E far enough `out on the inboard section yA tojgive ample clear'ance for a-suitable actuator F as the outboard wing sectioneB swings upwardly (see Figure 5). e e i Forthepurpose of `allowingthe outboard section B'to be swung up and down, a hinge bolt 25 is provided between the upper parts 12-14 of the front spar C (see Figure 4). Also, a hinge bolt 26 is arranged between the upper parts 16--18 of the rear spar D (see Figure 3).

ln Figures l and 2 of the drawings, I have shown the lower spar parts 13 and 17 as having outer ends 13a and 17a, respectively, which are oifset toward one another and terminate with the bottom portion of the airfoil edge 21a. However, the inner ends 15a and 19a of the lower spar parts and 19, respectively, project beyond the lower portion of the airfoil edge 23a so as to tit into spaces provided by the offset outer ends 13a and 17a, respectively, when the outboard section B of the wing is lowered into alignment with the inboard section A.

In order to lock the outboard section B in its extended vor active flying position, a pair of spaced-apart bushings 27-27 have been placed in openings provided in the inner end 15a of the lower spar part 1.5. These bushings are adapted to be brought into axial alignment with another pair of bushings 28-28 carried by the olset end 13a of the lower spar part 13 (see Figures l and 2). This will allow locking detents 29-29 to be inserted through registering pairs of bushings 28-27 and 28-27 to thus interlock the lower parts 13 and 15 of the front spar C.

Further rigidity is imparted to the outboard section B to hold it in prolongation with the inner section A by providing a pair of bushings 30-30 on the inner end 19a of the lower spar part 19, which are adapted to register with a second pair of bushings 31-31 carried by the offset end 17a of the lower spar part 17 (see Figures l and 2). Locking detents 32-32 are insertable through the registering pairs of bushings 31-30 and 31-30 to interlock the lower parts of the rear spar D in active position.

All of these locking detents and bushings may be made of a steel alloy, if desired, having the maximum hardness and strength. Also, the spars themselves should be strongly reinforced in the vicinity of the locking pins to withstand all possible stress.

The wing-lock toggle mechanism E previously mentioned includes a casing 33, which may be anchored to the inboard section A of the wing by any suitable means, for example, bolts 34. This casing is interposed between the front spar C and the rear spar D, and has a reciprocable rod 35 slidably guided therein to extend lengthwise of the wing.

For extending and contracting the detents 29--29 to thereby lock and unlock the spar parts 13-15, respectively, toggle links 36-36 are swingably connected to these detents by journal pins 37-37. The latter are guided in slots 38--38 fashioned in a cover plate 39 of the casing 33 (see Figure 7) so as to cause these pins to operate in a straight line and thus preclude the detents 29-29 from binding. Furthermore, these detents may be guided in bearings 48-40 provided in the casing 33.

The inner ends of the toggle links 36-36 are hinged to the reciprocable rod 35 by journal pins 41-41, which are guided for movement lengthwise of the wing by slots 42-42 formed in the cover plate 39 (see Figure 7).

As disclosed in Figures l and 2, a second set of toggle links 43--43 are hinged to the rod 35 at their inner ends by the journal pins 41-41, while their outer ends are connected by journal pins 44-44 to inner ends of extension links 45-45. The latter pins are guided in slots 46--46 provided in the cover plate 39 in parallel relation with the slots 38-38. Figures l, 2 and 7 disclose the outer ends of these extension links as being hingedly connected by journal pins 47--47 to the detents 32-32, while intermediate portions of the links 45-45 are slidably mounted in the casing 33.

It will be noted that when the outboard wing section B is locked down to the inboard section A, as in Figure l, the toggle links 36-36 and 43--43 are in perfectly straight alignments, making it impossible for the detents 29-29 and 32-32 to accidentally move out of the bushings 27-27 and 30-30, respectively.

However, when the central rod 35 is moved to the left until it occupies the position shown in Figure 2, the detents 29-29 are retracted from the bushings 2'7-*27 of the outboard spar part 15, but still remain in the bushings 28-28 of the inboard spar part end 13a. Likewise, the detents 32-32 are withdrawn from the bushings 30-30 of the outboard spar part end 19a, but remain in the bushings 31-31 of the inboard spar end 17a. The slots 38--38, 42-42 and 46-46 limit the inward and outward movement of the detents 29-29 and 32-32.

inasmuch as the locking detents move through only relatively short distances during travel out of the outboard spar parts, the wing-lock toggle mechanism E has been kept quite small; accordingly the extension links 45-45 have been provided to connect the detents 32-32 to the toggle mechanism. Also, this will minimize the necessary travel of the actuator F, which operates the rod 35, during locking and unlocking of the outboard spar parts.

Next l shall describe the details of the actuator F and a control mechanism G provided in connection therewith (see Figures 5 and 6). This actuator has been illustrated as being selected from a hydraulic type. lt includes a cylinder 48 having a piston 49 slidably arranged therein. This cylinder may be swingably connected by a hinge pin 50 to a bracket 51, which in turn is secured to the lower portion of the outboard wing section B by any suitable means, such as a reinforcing plate 52 anchored to the spar parts 15 and 19 (see Figures 1-2 and 4-5).

As clearly illustrated in the drawings, a piston rod 53 is reciprocably mounted in the cylinder 48, with its inner end being secured to the piston 49 and its outer end connected by a pivot pin 54 to the outboard portion of the toggle mechanism rod 35. During the initial movement of the piston rod 53 to the left in Figure 1, the toggle mechanism E is actuated to unlock the outboard spar parts 15--19 (see Figure 2); and as this piston rod continues its uninterrupted outward travel,

the actuator F raises the outboard wing section B into folded position, as illustrated in Figure 5. Of course, reverse movement of the piston rod will operate to first lower the outboard section B into alignment or prolongation with the inboard section A; and, thereafter, interlock the two sections by actuating the wing-lock mechanism E, all in one continuous movement of the piston rod.

Turning to Figures 5 and 6, the control mechanism G has been shown diagrammatically as including a storage reservoir 55 containing iluid 56. The latter may be withdrawn by a pump 57 through a pipe 58, and delivered under pressure to an intake line 59 of a valve body 60. Within this body there is mounted a swingable vane 61, which is operable by handle 62. This body 60 and vane 61 dene interior passageways 63 and 64 through which the iluid may ow.

Flexible hoses 65 and 66 lead from the valve body to inboard and outboard ports 65a and 66a, respectively, at the opposite ends of the cylinder 48 (see Figures 5 and 6). These ports communicate with the interior bore of the cylinder.

When the handle 62 is disposed in the full-line position shown in Figure 5, designated by the legend Up, luid will flow from the pump 57 through the intake line 59 to the interior passageway 63, and thence through the hose 66 to the outboard port 66a of the cylinder 48. This will result in extending the piston rod 53 relative to the cylinder 48, causing the toggle mechanism E to unlock the outboard section B and folding the latter upwardly. Simultaneously, fluid disposed in the interior of the cylinder 48 inboard of the piston 49 will be forced terruption.

through the hose r65, through the interior passageway catch 68 on the lhandle "62, 'which must -be released bc'- fore the latter -c'anbe moved to Upor wing-fold iposition. This safety feature will prevent the pilot from 'r'aisingt'he wing accidentally,tins'tead ofthe'landih'g gear,

67 for return to 'the reservoir 55.

'After Athe outboard section B 4swings intokalignment with the inboard section A, the toggle mechanism;E will be moved from the disposition shown in Figure 2 into that illustrated in Figure 1, all in one continuous operation, causing the detents 29-29 and 32-32 to interlock the outboard and inboard spar parts.

In Figure 4, the hinge bolt 25, which connects the upper front spar parts 12-14, has been shown as being arranged vertically above substantially the midpoint between the locking detents 29-29. The same is true of the hinge bolt 26 relative to the locking detents 32-32 in Figure 3. Of course, the bolts 25-26 are arranged in axial alignment with one another. Figure 5 clearly discloses the mechanical advantage obtained by the hydraulic cylinder 48 in swinging the outboard section B of the wing about these pivot bolts to thereby swing the outboard section with the minimum amount of effort.

The plate 39, preferably of steel, telescopes over the journal pins 37-37, 41-41 and 44-44; and, also, is arranged above the toggle links 36-36 and 43-43. Accordingly, this plate will take any upward strain as the outboard wing section B is swung beyond top dead center, that is, counter-clockwise from the position shown in Figure 5, thereby relieving the toggle mechanism E of undue strain. This plate may be secured in place by the bolts 34 previously described.

Summary The actuation of my foldable aircraft wing with mechanism for operating and locking the outboard section thereof is summarized briefly as follows:

Assuming that the outboard wing section B is arranged in its active flying position, as shown in Figure 1, and locked down to the inboard section A, and that the pilot desires to fold the outboard section upwardly, this result is accomplished by releasing the safety catch 68 and swinging the handle 62 to Up position (see Figure 5).

With the pump 57 operating at this time, fluid 56 will be withdrawn from the reservoir 55, and forced through the line 59, interior passageway 63, hose 66 and port 66a to the interior of the cylinder 48. The fluid thus delivered to the cylinder will extend the piston rod 53. Initially the latter will push the reciprocable rod 35 of the wing-lock toggle mechanism E into the position illustrated in Figure 2, thereby withdrawing the detents 29*29 and 32*32 from the outboard spar parts 15 and 19, respectively.

Now further outward extending of the piston rod 53 `relative to its cylinder 48 will cause the outboard section B of the foldable wing to swing upwardly into the position shown in Figure 5. The upward swinging of this wing section follows the unlocking thereof without in- Of course, fluid contained in the cylinder "6 '48 inboard 'of therpi'stohi49 will befforctl tholigh ithe hose '65, interior tpassage 6'4 and pipe "67 back to thie rservoir.

Subsequent return Ito fthe btbord 'section 'B "into lowered extended arrangement relative to 'the :inboard tsection 4'A may be Aaccomplished by swinging the handle -62 into DownWpositionCseeFigure 6). This will'c'ause 1the pump 57 'to force uidunderfpressure thoughitheitror passageway '64, 'hose 65 'and port'6'5a y`to {helin- 'board end of the cylinder '48. Simultaneously therewith, Jiiuid `will 4beiexhauisteizl lfrom Athe utbordfport 66a, hose '66, interior passageway 63 4'and retuned LAto theresrvoir `byjthe `pipe l"67.

This will'result infretracting the pistonrodSS Pwith're- "spct to the cylinder 48, `-'causing the outboard iwin'g sec- -ti'ontBto be'loweredinalignmentwith'theinboa'rdsection A. During 'the latter-p`artiof this inward tr'avefof'tlie -pisto'n rod,'tl ie rod 35 andthe toggleflink's 36136nd 4'3-43 'will '-move vthe detents 29;29 vanti 32:32 "outwrdly yuntil 'these -detents interlock the `outboard and 'inboard sections` of `Athe wingiuinone continuous op- -eration and `with 'theminimuin -of effort.

1. In a Itoldable aircraft -wing: 'inboard ani outboard wing "sections, the latter 'being l`sv'virigable relative eto lthe former between ight and upwardly-folded positions; the outboard section, when in ight position, projecting lengthwise in a lateral direction beyond an outer end of the inboard section; a spar extending lengthwise of the wing, and including inboard and outboard spar parts secured to the inboard and outboard wing sections, respectively; hinge means securing these spar parts together, and including a pivot about which the outboard wing section may be swung between flight and upwardlyfolded positions; a wing-lock mechanism for locking and unlocking the outboard spar part with the inboard spar part; and common means for unlocking said mechanism and then sequentially raising the outboard wing section into folded position in a continuously-folding operation; said common means being operable for lowering the outboard wing section into flight position and sequentially locking said mechanism in a continuous wingextending operation; said wing-lock mechanism including a toggle operated by said common means, and further including detents actuated by the toggle; said detents being movable into an advanced position to interlock the inboard and outboard spar parts, and being retractable to unlock said parts; said toggle being movable into a position to prevent the detents from being retracted accidentally into unlocked position.

2. In a foldable aircraft wing: inboard and outboard wing sections, the latter being swingable relative to the former between flight and upwardly-folded positions; the outboard section, when in flight position, projecting lengthwise in a lateral direction beyond an outer end of the inboard section; front and rear spars extending lengthwise of the wing, each including inboard and outboard spar parts secured to the inboard and outboard wing sections, respectively; hinge means securing inboard and outboard spar parts together, and including pivots about which the outboard wing section may be swung between flight and upwardly-folded positions; a wing-lock mechanism including toggle-actuated detents for locking and unlocking the outboard spar parts of the front and rear spars with the inboard spar parts of the front and rear spars, respectively; and common means for unlocking said mechanism and sequentially raising the outboard wing section into folded position in a continuous wing-folding operation; said common means being operable for lowering the outboard wing section into flight position and sequentially locking said mechanism in a continuous wing-extending operation.

3. In a foldable aircraft wing: inboard and outboard wing sections, the latter being swingable relative to the former between flight and upwardly-folded positions; the

section; front and rear spars extending lengthwise of the Wing, each including inboard and outboard spar parts secured to the inboard and outboard wing sections, respectively; hinge means securing inboard and outboard spar parts together, and including pivots about which the outboard Wing section may be swung between ight and folded positions; a wing-lock mechanism located in the inboard wing section between the front and rear spars; said mechanism including a reciprocable rod and at least a pair of toggle links pivotally secured to said rod to be operated thereby; these toggle links extending in opposite directions towards the spar parts; each link having a ldetent attached thereto; the detents being movable into advanced positions by the toggle links and said rod to interlock the inboard and outboard spar parts, and being retractable to unlock said parts; and an actuator accommodated in the outboard wing section; said actuator including a pair of members, one being extendible relative to the other; the extendible member being connected to the reciprocable rod of the wing-lock mechanism, and the other member being anchored to the outboard wing section; the extendible member being movable for retracting said detents from the outboard spar parts and sequentially raising the outboard Wing section into folded position in a continuous wing-folding operation; said extendible member being retractable for lowering the outboard Wing section into flight position and sequentially advancing the detents for interlocking the inboard and outboard spar parts in a continuous wing-extending operation.

4. The combination as set forth in claim 3, in which two pairs of said toggle links are pivotally attached to said reciprocable rod for operation thereby; two oi the links having detents positioned for interlocking the inboard and outboard parts of the front spar; the other two links being provided with detents disposed for interlocking the inboard and outboard parts of the rear spar.

References Cited in the tile of this patent UNITED STATES PATENTS 2,290,850 Umschweif July 21, 1942 2,343,645 Dickenson et al Mar. 7, 1944 2,536,086 Pomykala Jan. 2, 1951 FOREIGN PATENTS 420,209 Great Britain Nov. 22, 1934 490,964 Great Britain Aug. 24, 1938 

